Background: A percutaneous intravascular cardioverter-defibrillator (PICD) has been developed with a right ventricular (RV) single-coil lead and titanium electrodes in the superior vena cava (SVC)-brachiocephalic vein (BCV) region and the inferior vena cava (IVC).
Objective: To compare defibrillation thresholds (DFTs) of the PICD with those of a conventional ICD in humans.
Methods: Ten patients with ischemic cardiomyopathy and ejection fraction ≤35% were randomized to initial testing with either PICD or conventional ICD. A standard dual-coil lead was positioned in the RV apex. If randomized to PICD, the device was placed into the vasculature such that 1 titanium electrode was positioned in the SVC-BCV region and the second in the IVC. For PICD DFTs, the RV coil of the conventional ICD lead was connected to the PICD mandrel [shock vector: RV (+) to SVC-BCV (-) + IVC (-)]. When testing the conventional ICD, a subcutaneous pocket was formed in the left pectoralis region and the ICD was connected to the lead system and positioned in the pocket [shock vector: RV (+) to SVC (-) + active can (-)]. Each device was removed before testing with the other. A step-down binary search protocol determined the DFT, with the initial shock being 9 J.
Results: The mean PICD DFT was 7.6 ± 3.3 J, and the conventional ICD system demonstrated a mean DFT of 9.5 ± 4.7 J (N = 10; paired t test, P = .28).
Conclusion: The intravascular defibrillator has DFTs similar to those of commercially available ICDs.
Keywords: BCV; DFT; Defibrillation threshold; ICD; IVC; Implantable cardioverter-defibrillator; Intravascular defibrillator; PICD; RV; SVC; VF; brachiocephalic vein; defibrillation threshold; implantable cardioverter-defibrillator; inferior vena cava; percutaneous intravascular cardioverter-defibrillator; right ventricle/ventricular; superior vena cava; ventricular fibrillation.
Published by Heart Rhythm Society on behalf of Heart Rhythm Society.